胆酸钠自组装行为的小角X射线散射研究  

Study on self-assembly behavior of sodium cholate by Small-angle X-ray scattering

作　　者：李博楠 李天富[1] 刘荣灯[1] 王子军[1] 刘蕴韬[1] 陈东风[1] LI Bonan;LI Tianfu;LIU Rongdeng;WANG Zijun;LIU Yuntao;CHEN Dongfeng(China institute of atomic energy, Beijing, 102413)

机构地区：[1]中国原子能科学研究院,北京102413

出　　处：《光散射学报》2020年第4期343-347,共5页The Journal of Light Scattering

基　　金：国家自然科学基金面上项目(11475267)。

摘　　要：胆酸钠相较于常规表面活性剂有着特殊的自组装行为,这是由于胆酸钠具有独特的刚性类固醇骨架以及双亲面式结构导致的。通过小角X射线散射并辅以等温滴定量热实验、Zeta电位测量对胆酸钠的自组装行为进行表征,发现了胆酸钠受浓度变化影响的自组装行为发生变化以及胆酸钠自组装体存在最大尺寸。分析讨论了导致自组装行为变化的两种驱动方式,即疏水作用驱动的结合方式与分子间羟基形成氢键的结合方式,并发现在20 mg/mL浓度范围时,两种驱动方式达到平衡,随着浓度进一步升高,逐渐变为以分子间羟基形成氢键的驱动方式为主导。通过对小角X射线散射结果进行模型拟合分析,得出具体的胆酸钠形貌尺寸信息,胆酸钠自组装体长轴半径在13.5~41.2之间,短轴半径在9.6~11.4之间,达到40 mg/mL浓度范围时,胆酸钠自组装体达到最大尺寸不再继续增大。Compared with conventional surfactants,sodium cholate has a special self-assembly behavior,which is due to its unique rigid steroid skeleton and amphiphilic structure.The self-assembly behavior of sodium cholate was characterized by small-angle X-ray scattering,isothermal titration calorimetry and zeta potential measurement.Aggregation driving forces of self-assembly behavior change are discussed,It was found that in the concentration range of 20mg/mL,hydrophobic interaction and hydrogen-bond interaction reached a balance.With the increase of concentration,the driving forces of hydrogen bond gradually became dominant.Through the model fitting analysis of small angle X ray scattering results,the specific shape and size information of sodium cholate was obtained,The long axis radius of sodium cholate self-assembly is between 13.5-41.2,and the short axis radius is between 9.6-11.4.When the concentration reaches 40 mg/mL,the self-assembly of sodium cholate reaches the maximum size.

关 键 词：生物表面活性剂 胆酸钠 自组装 小角X射线散射 模型拟合 

分 类 号：Q74[生物学—分子生物学]